electric line of force

例句：

1. 1. The electric line of force between the two poles is what determines the strength of the magnetic field.
   两个极之间的电流力线决定了磁场的强度。
2. 2. The electric line of force in a capacitor can be used to calculate its capacitance.
   电容器中的电流力线可以用来计算其电容。
3. 3. The electric line of force is a fundamental concept in electromagnetism.
   电流力线是电磁学中的基本概念。